The 1.5KE30CABULK: That 1500 W rating is the energy the die can absorb in a single surge event — it sets the survivability ceiling for the transient, not the steady-state dissipation. For a 36 A peak pulse current (Ipp), the clamping voltage holds at 41.4 V max, meaning a 25.6 V nominal rail sees the spike clipped just above 41 V before the diode conducts the surge to ground.
Standoff, breakdown, and clamping — the voltage stack
Breakdown starts at 28.5 V min, so a 24 V rail riding at 25 V stays below the avalanche threshold. The gap between standoff and clamp (roughly 16 V) is the protection window — tighter than a generic MOV for this rail voltage.
Through-hole DO-201 axial — mounting and thermal path
The DO-201AA (DO-27) axial leaded package suits point-to-point wiring or through-hole PCB mounting. The junction temperature range spans -65°C to 175°C, which covers most industrial and telecom enclosures without derating. The axial body allows the diode to be inserted into a board or wired inline with heat-shrink — useful for retrofitting protection into an existing harness without a board spin.